Zero single points of failure. Oracle RAC depends on a central storage area. So, if that storage area fails, the database is down, even if all the processing nodes are still up. (Obviously, you can make the storage area itself redundant with various strategies. But, that's an additional step that needs to be taken.)

With NDB clustering, every processing node is also a storage node. So, the failure of any single point will not bring the database down.

Every article I've ever read on the concept of clustering says that this is the most robust architectural model.

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We are the carpenters and bricklayers of the Information Age.

Then there are Damian modules.... *sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon. - flyingmoose

I shouldn't have to say this, but any code, unless otherwise stated, is untested